Paving machine



R. D. BAKER PAVING MACHINE Feb. 5, 1946.

Filed Aug. 27, 1942 9 Sheets-Sheet 1 INVENTOR. /of/er D. AKE/ BY ,WW

ONE Y R. D. BAKER PAVING MACHINE Feb. 5, 1946.

Filed Aug. 27, 1942 9 Sheets-Sheet 2 Y myn TTONE Y INVENTOR. oE/er A KE/ Feb. 5, 1946, R. D. BAKER 2,393,954

PAVING MACHINE Filed Aug. 27, 1942 9 Sheets-Sheet 3 Feb. 5, 1946. R. D. BAKER 2,393,954

PAVING MACHINE Filed Aug. 27, 1942 v 9 sheets-sheet e INVENIOR. P05/5R7- 0 5A KE/ ATTORNEY R. D. BAKER PAVING MACHINE Feb. 5, 1946.

Filed Aug. 27, 1942 9 Sheets-Sheet 7 LM! I#127 .Nlmgar I" INVENTOR. /Pof/QT 0 BA KE/P BY l Tro/e/VEY Feb. 5, 1946. R, D BAKER 2,393,954

PAVING MACHINE Filed Aug. 27, 1942 9 SheellS-Sheeb 8 INVENTOR.

7' ORNE Y Patented- Feb. 5, 1946 UNITED sTATEs PATENT OFFICE PAVING MACHINE Robert D. Baker, Birmingham, Mich. Application August 2K7, 1942, Serial No. 456,318

(Cl. 94-46l be readily manipulated from its working position y 9 Claims.

'This inventionv relates to improvements in paving machines of the type employed to lay and l compact asphalt and concrete pavements.

The present invention is an improvement over the paving machine disclosed and claimed in U. S. Letters Patent No. 2,245,426, issued June 10, 1941, to Robert D. Baker, entitled Paving machine.

The primary objectfof this invention is to irnprove the effectiveness, operability and maneuverability of paving machines of the class described whereby they may more readily and more accurately accomplish the laying and compacting of asphalt or concrete pavements to the desired density, thickness and grade.

Another object of the invention is to provide a paving machine of the class described wherein improved suspension of the compacting mechanism employed and adjustment thereof during the operation of the machine admits of extremely fine control of the thickness and grade of pavement laid thereby. I

Another object of the invention is to provide an improved paving machine wherein the traction membersv carrying the main and variable weight of the machine travel on the rough grade and the compacting mechanism is carried in floating pivotal towed relationship with respect to the traction members whereby to reduce to a minimum the variance in grade, smoothness and density of the finished pavement laid thereby.

Another object of the invention is to provide an improved paving machine employing compactors having a combined elliptical and rocking motion wherein the compaction members are held to grade by gage means traveling on the finished roadway and wherein the compaction members relieve the pressure of the gage means on the finished roadway.

Another object of the invention is to provide an improved paving machine employing gage means traveling on the finished roadway which is self positioning to ride on the transverse contour of the said finished roadway.

Another object of the invention is to provide a paving machine wherein accurate quantitative control of paving material is accomplished by rst windrowing the paving material from the hopper, then distributing it laterally, and finally striking it off' prior to compaction, thus assuring uniformity of pavement laid and compacted.

Another object of the invention is to provide an improved paving machine capable of transportation under its own power and which may to its transport position and vice versa.

Other objects of the invention will become apparent by reference to the following detailed description taken in connection with the accompanying drawings, in which:

Fig. 1 is a plan view of a paving machine embodying the invention. y

Fig. 2 is a side elevational view of the paving machine illustrative of the invention disclosed in Fig. 1 showing the paving machine in its Working position.

Fig. 2-A is an enlarged fragmentary sectional view taken on the line 2-A-2-A of Fig. 2-B showing a preferred free floating pivotal connection of the floating sub-frame to the main frame.

Fig. 2-B is a detailed horizontal sectional view taken on the line 2-B-2-B of Fig. 2A.

Fig. 2-C is an enlarged vertical sectional view taken on the line 2-C-2C of Fig. 2 showing the spring loaded floating side forms carried by the floating sub-frame.

Fig. 3 is a side elevational view similar to Fig. 2 with the exception that the paving machine is in'its transport position.

Fig. 4 is an enlarged fragmentary side elevational view of the forward portion of the paving machine disclosed in Figs. 1 to 3 inclusive.-

Fig. 5 is an enlarged fragmentary side elevational view -of the rear portion of the paving machine disclosed in Figs. 1 to 3 inclusive.

Fig. 6 is a fragmentary rear elevational view of the paving machine taken on line 6-6 of Fig. 5.

Fig. 7 is an enlarged fragmentary plan view of the compacting mechanism preferably employed l and controls therefor.

Fig. 8 is a fragmentary sectional View taken on the line 8-8 of Fig. 7 looking at the front of the compaction members.

Fig. 9 is an enlarged cross sectional view of the compacting mechanism preferably employed including in dot and dash lines a diagrammatic representation of the compaction action of the compaction members.

Fig. 10 is a fragmentary plan view of a compaction member taken on the line Ill-I0 of Fig. 9.

Fig. 11 is a diagrammatic view showing the drive mechanism employed in the illustrative embodiment of the invention herein disclosed.

Figs. 12 and 13 are fragmentary vertical sectional views taken along the longitudinal center of the paving machine showing the adjustment of the compaction members while increasing or decreasing the thickness of the pavement respectively.

In the following description of th'e invention, like numerals refer to like and corresponding parts throughout the several drawing figures. A brief general description of the improved paving machine illustrating the invention will be given first and followed by a more detailed description of the .construction and operation of the paving machine.

General description The particular paver selected as illustrative of the invention and disclosed in detail in the drawings comprises a main frame 25 preferably supported for mobility on front'wheels 26 and rear caterpillar endless treads 21, both' of which travel on the finished grade or fine-graded terrain 200 over which pavement is to be laid. The said main frame 25 carries a transversely disposed hopper 28 from which concrete or asphalt .mixes are fed by gravity into a windrow 14 after agitation and lateral accumulation by suitable conveying type screws 29. A floating sub-frame 30 is connected at its forward end by vertically floating transverse pivots 3| to the main frame 25 preferably within the middle third of the distance between the front wheels 26 and the caterpillar treads 21. The said floating sub-frame 30 is provided with gage wheels 32 at the rear thereof which ride on finished pavement laid by the paver.

A compactor sub-frame 33 is suspended in vertical adjustable and transverse tiltable relationship from the floating subframe 30 and is rearwardly disposed with respect to transverse distributing screws 34 carried by the said floating sub-frame 30; the distributing screws 34 and a strike plate 35 carried by the compactor subframe 33 serve to assure an even flow and proper quantity of paving material from a windrow thereof to compaction members 36 carried by the said compactor sub-frame 33. The said compaction members 36 are preferably mounted and powered to compact and smooth mixes spread thereahead by a rapid combined elliptical and rocking movement which has been found to produce an extremely dense finished pavement having substantially no voids therein. The said compaction members 36 are so formed as to advance surplus material fed thereto thereahead during their combinedelliptical and rocking movement, only accepting for compacting sufiicient material to assure maximum density of the pavement being laid thereby.

Side forms 31 arepreferably carried by the floating sub-frame 30 alongv both sides thereof and are mounted on the oating sub-frame 30 in such a manner as to be constantly urged against and fioat on and follow the ne-gradeterrain or semi-finished surface upon which a concrete or asphalt pavement is laid by the machine.

The compaction members 36 are constructed to admit of adjustment to provide a crowned roadway if desired. More important, the rockers struts of the compaction members 36 are movable vertically during the operation of the paver whereby to admit of proper and accurate establishment/ of the grade and thickness of pavement laid by the improved paving machine during the paving operation, the finished pavement being compacted dense and substantially voiclless.

A detailed description of the construction and operation of the improved paver follows.

Main frame and mobile means The main frame 26 is preferably composed of a pair of longitudinally disposed laterally spaced box girders 40 and forward, central and rear cross members 4|, 42 and 43 respectively spanning transversely between the said longitudinal frame members 40. The rear of the main frame is supported on caterpillar endless treads 21 by means of a pair of laterally spaced transversely disposed pivots 44 extending through laterally spaced brackets 45 depending from suitable framing provided in' the main frame 40 and through holsters 46 secured to the top of the laterally spaced side rails 41 of the endless caterpillar treads 21. Each' endless caterpillar tread 21 is composed of a pair of laterally spaced side rails 41 through which front and rear sprocket shafts 48 and 49 are journaled on take-up bearings 50, the said sprocket shafts 48 and 49 having caterpillar tread sprockets 5| keyed thereon. Although not shown, the usual caterpillar tread idlers may be employed to prevent the lower run of the caterpillar endless treads 21 from deflecting between the caterpillar tread sprockets 5|. Each caterpillar endless tread 21 has a drive sprocket 52 keyed to the rear tread sprocket shaft 49 to admit of driving the Vsame by such means as a chain drive, clutches, and a transmission hereinafter described in detail.

The front end of eachlongitudinally disposed main frame member 40 extends a considerable distance forward from the forward cross member 4| and is supported on a front wheel 26 preferably having a tire 53 thereon. Each front wheel is rotatably mounted on an axle 54 fixed through the lower bifurcated end 55 of a vertically disposed spindle 56 journaled through a suitable bracket 51. Steering of the paver is accomplished by turning of the said spindles 56 by such means as a conveniently located steering wheel 56 mounted on a steering column 59 connected to worm and pinion gearing 60 adapted to turn a transversely disposed steering shaft 6| which is coupled by arcuately movable levers 62 and 63 disposed on opposite ends of the said transverse steering shaft 6| to a pair of steering rods 64 linked at their rear ends to the said arcuate levers 62 and 63, linked at their center to a pivot bar 65, and linked at their front ends to steering arms 66 keyed to the upper ends of the said wheel spindles 56, all as best shown in Figs. 1, 2, 3, and 4.

The main frame 25 is provided with secondary framing members secured to the longitudinal girders 40 and cross members 4|, 42 and 43 to provide support for operating platforms 61 and 68 and for the hopper and drive mechanism hereinafter described in detail.

Hopper and agitator A suitably shaped closed bottom hopper 28 preferably constructed of sheet steel and reinforced as required extends substantially across the entire width of the paver and is suspended from the longitudinal box shaped side members 40 and the forward cross member 4| of the main frame 25 as indicated in Figs. 1, 2, 3 and 4, Adjustable gates 10 and 1| located adjacent each other on opposite sides of the transverse center of the hopper 28 and each operable by a system of levers 12 and 13 respectively provide means for regulating the flow of material from the hopper 28 into a desirable shaped windrow 14 indicated in Fig. 2.

Conveying type agitator and collector screws 29 loc-ated transversely in the hopper 28 near the bottom thereof and powered through sprockets 15, chains 18 and independent clutches 11 operated by clutch levers 18 and 1 8, all as hereinafter described in detail, agitato paving material deposited in the hopper 28 and collect, it at l and continuously to the windrow 14 through the y gates 10 and 1| during the operation of the paver. l

The agitator and collector screws 28 may be omitted if the hopper 28 is constructedvwith suitably sloped sides or otherwise to assure paving material therein to flow to the gates 10 and 1|.

Floating sub-frame and gage means 'Ihe floating sub-frame 30 is floatingly pivoted at its front end onV transverse pivots 3| to longitudinally disposed box girders 40 of the main frame 25 preferably at a point within the middle .third of the distance between the caterpillar tread pivots 44 and the front wheels 26 and is composed of a pair of side members 80A and forward and rear transverse members 8| and 82 between and over which short longitudinal members 83, 84 and 85 are connected.

By referring to Figs. 2-A and 2-B, it will be noted that each of the transverse pivots 3| take the formA of a shouldered bolt which extend through a plate 3|0 secured in depending relationship from the outside of the box girder 40 employed as main frame members'25. A ball bearing 3|| is mounted on the said transverse pivot 3| outside and in spaced relationship to the said plate 3|0 in such a manner that the outer race of ythe said ball bearing is free to rotate. The forward end of the side .member 80 of the floating sub-frame 30 is provided with a vertically disposed slot 800 through the web 80| thereof through which the transverse pivot 3| and the ball bearing 3|| thereof are .telescoped. Washers 3|2, 3|3 and 3|4 center the web 80| of the side floating sub-frame member 80 transversely on the outer race of the ball bearing 3| and a nut 3| 5 secures the component parts of each of the transverse pivots in assembled relationship, The said vertically disposed slot 800 through the web 80| of the side floating subframe member 80 is slightly wider than the diameter of the outer race of the ball bearing 3| which permits the said outer race of the ball bearing 3| to roll on the edge 802 of the floating sub-frame side member 80 when the floating subframe 30 is pivotally towed by the main frame 25; thus compensating for tilting of the main frame 25 with respect to .the floating sub-frame 30, the latter being supported by the compaction members 36 on the finished pavement,

cantilever gage wheel brackets 86 extending rearwardly from two of the said spacer members 84 are supported by a pair of Wide tread laterally spaced gage wheels 32 which are each rotatably mounted on a transversely disposed axle 81 extending between the depending ends of an arched channel frame 88, which frame is pivoted to the said cantilever bracket 86 by means of a longitudinally disposed pivot 89 and a vertically disposed king pin 880. The king pins 880 provide a. caster-like action to the gage wheels 32 and together with the longitudinal pivots 88, prevent the gage wheels 32 from scumng or gouging into pavemerxitfreshlylaid by the paving machine and permit the machine to be steered easily. A stop 88 on each side of each cantilever` bracket 88 prevents excessive pivoting of the gage wheels 82 on their longitudinally disposed pivots 88. Anv equalizing spring 8| fixed to each of said cantilever brackets 88 engages the top of the arched channel frame 88 pivoted thereto and constantly urges the bracket 88 and the gage wheels" 32 to their normal position with the tread of the gage wheels 82 on a plane transversely parallel to the floating sub-frame 30.

The foregoing construction permits the floating subframe 30 to be towed in pivotal floating relationship from thegmain frame 25 with the gage means or wheels 32 of the said floating subframe 30 traveling on the finished freshly laid pavement; the said gage Wheels 32 being resiliently maintained to rotate on a plane trans- `versely parallel to the floating sub-frame 30.

The gagewheels 32 are self-positioning transversely on pavement being laid to accommodate themselves to a crowned or laterally sloped pavement when a crowned or laterally sloped pavement is laid by the paving machine. Furthermore, the floating pivotal connection of the floatingsub-frame 30 to the main frame 25 compensates for inequalities in the sub-grade 200 and permits the compactors to lay paving material to the desired grade without undue distortion of the floating sub-frame 25.

The paver is brought from its operating position shown in Fig. 2 to its transport position shown in Fig. 3 by means of hydraulic jacks 84 mounted on each side of the main frame and engaging suitable lift brackets 300 provided on each side of the floating sub-frame 30, the said hydraulic jacks 84 being employed to lift or lower the said floating sub-frame 30 about its transverse pivots 3| to and from its transport position shown in Fig. 3.

Side forms The improved paver preferably carries its own side forms 31 which are resiliently suspended from the floating sub-frame 30 by means of suitable tubular struts 82 welded to the side members 80 of the said floating sub-frame 30 and pistons 83 .welded to the side forms 31 and reciprocatingly mounted in the said tubular struts 82, all as best shown in Figs. Z-A and 6. The said pistons 83 are spring loaded by compression springs 830 to provide vertical resiliency and to constantly urge the side forms 31 against the rough grade over which or adjacent to pavement being laid by the paver. The side forms 31 must not interfere with the riding of the gage wheels 32 on the freshly laid pavement, therefore, the springs 930 must not be so heavy as to lift the rear end of the floating sub-frame 30.

compactor sub-frame The compactor sub-frame 33 which carries the compaction members 36 is composed of a forward transversely disposed channel member 85 and a rear transversely disposed VI-beam 86 held in the desired spaced relationship' by a plurality of longitudinal struts 81 and 88.

The said compactor sub-frame 33 is suspended at each end from the floating sub-frame 30 by means of a pair of suitable adjustable hanger rods 88 pivotally connected at their lower ends tothe top of the compactor sub-frame 33 and at their upper ends to a pair of arcuate levers |00 keyed to a compactor sub-frame hanger shaft |0| iournaled through suitable bearings |02 secured to the top of the forwardand rear transverse' floatingsub-frame members 3I and 32respectlvely. cantilevered to rotate each compactor sub-frame hanger shaft which, through the said arcuate levers |00 keyed thereto, are employed to raise and lower the compactor sub-frame 33 and the compactor members 32 carried thereby witherespect to the oating sub-frame 30. By raising Transverse distributor and strike Carried by the floating sub-frame 30 immediately forward of the compactor sub-frame 33 is a pair of transverse distributor screws 34 which distribute laterally pavingl material from the windrow 14. The said distributor screws 34 are opposite hand each side of the transverse center of the paver and are turned by means of sprockets |09, chains ||0 and independent clutches operated by clutch levers H2 and ||3, all as hereinafter described in detail.

The strike 35 is mounted in depending verticalv adjustable relationship from brackets 350 extending forward from the compactor sub-frame 33, the said strike-plate 35 having vertically disposed slotted apertures I4 therethrough to receive securing bolts ||5, all as best indicated in Figs. 6, 9 and 10. By adjusting the strike plate 35 in accordance with the compressibility` of paving material to be laid by the paver, the proper am-ount of paving material will be furnished to the compaction members 36; the distributor screws 34 providing an even supply of material from the windrow 14 along the said strike 35. By making the strike plate 35 movable with the compactor sub-frame 33, the proper amount of paving material will flow to the compaction members 36 in accordance with the adjustment of A gear box |03 and hand lever |00 the said compaction members 36 during the operation of the paver.

compactor mechanism The. improved compactor mechanism preferably employed comprises a. plurality of compaction members 36 each composed of a suitable curved generally horizontal shoe |20 and a generally vertical bulldozer plate |2| extending upwardly from the toe of the said shoe |20, both of which are removably secured to the base |22 of the compactor arm casting |23 which has its head |42 secured to a pair of eccentrics |25 mounted on the compactor drive shaft |26 supported on suitable bearings secured to the rear transverse I-beam 96 of the compactor sub-frame 33; the said compactor drive shaft |26 is driven by means.` of a sprocket |21 and chain |20 as hereinafter described in detail. Adjacent pairs of eccentrics |25 are preferably staggered |80 degrees around the compactor drive shaft |26 `to eliminate excessive vibration or jumping of the compactors 36, compactor sub-frame 33 and floating sub-frame 30 with respect to the roadway being laid by the machine whereby to avoid wash boarding of the-finished roadway.

The base |22 of each compactor' arm y|23 is suspended from the forward transverse channel frame member 95 of the compactor sub-frame 33 by means of a pair of pivot bars |29 linked by upper transverse pivots 30 to brackets |3| welded to a transverse compactor elevator member |32 mounted on the said transverse channel frame member 95 for vertical sliding movement with respect thereto and linked by a pair of lower transverse pivots |33 to the top of the base |22 of the compactor arm |23. By such suspension and mounting the compaction members 36 are moved to effect an ironing action on the material. In other words, the eccentric |25 moves the compaction member 36 forwardly and rearwardly, causing it to simultaneously oscillate about the pivot |33 and simultaneously causing it to oscillate about the pivot |30. It will be appreciated that when the high point of the cam |25 isin substantial alignment with the length of the arm |23 the compaction member 36 will have been moved to its extreme forwardly position. From this point as the cam |25 rotates in the direction of the arrows shown in Fig. 9 during first portion of the movement oscillation of the com-A paction member 36 and particularly the'shoe |20 thereof will occur aboutthe pivot |33, causing the toe Y of the shoe 20 to be depressed to compact the material therebelow and to slightly raise the heel X, the movement of the latter in such case being very slight in view of the fact that it projects to a much smaller extent rearwardly of the vertical line passing through the pivot |33 than the toe Y projects forwardly of such line.

As the eccentric |25 continues to turn in the direction stated from its forwardmost position it will continue to oscillate the shoe |20 about the pivot |33, but at a successively reducing rate, and will be drawn rearwardly at an increasing rate while swinging about the pivot |30. When the high point of the eccentric |25 reaches a position at right angles to the length of the arm |23 substantially no oscillation of the shoe |20 about the pivot |33 will occur but al1 of the movement will occur about the, axis of the pivot |30 which being locatedk in advance of the pivot |33 will have a tendency to slightly raise the compaction member 36 and shoe |20 as a whole. As the eccentric |25 continues to move from the last described position to a position in which its high point is in line with the arm |23 but on the opposite side thereof from the axis of the shaft |26, the compaction member 36 and shoe 20 thereof will have been moved rearwardly to its fullest extent and oscillation of the compaction member 36 and shoe |20 with but a slight amount of movement about the pivot |30 will occur, the toe Y of the shoel |20 being lifted in such case and the heel X being slightly depressed.

From the last-mentioned position as the eccentric 25 continues to rotate in the direction of the arrows in Fig. 9 the compaction member 36 with the toe Y of the shoe 20 in elevated position will be moved forwardly to gather another mass of the soft material below it for compaction in the subsequent cycle and the heel X of the. shoe |20 in such case will be slightly depressed during such forward movement. This last-mentioned movement of the heel of the shoe is desirable in that inasmuch as it is sometimes found that in the rearward and downward movement of the -toe Y of the shoe 20 a tendency to form a ripple in the surface of the roadway is observed and where such a tendency occurs the above described movement of the heel X of the shoe |20 during its forward movement serves to effectively iron out this ripple. The toe Y of the shoe |20 thus serves primarily as a compacting surface and While its rearward and downward movement does provide an important ironing action on the surface of the roadway compacted thereby .the above described movement of the heel X of the shoe |20 is of major importance in providing the smooth, even surface desired on the final road surface.

During the foregoing cycle of operation of the compaction members 36, the bulldozer 2| urges all material ahead of the compaction members 36 except that material which slides under the compactor shoe |20. Any material which becomes positioned under the shoe |20 of the compaction members 36 becomes compressed by the combined swinging and rocking movement therelar drive mechanism shown is preferably powered by a single source of power such .as a gasoline or Diesel engine |50 through a main clutch 15| controlled by a main clutch lever |52 operated through a remote control linkage generally designated by the numeral |53 in Fig. 1. A main transmission |54 coupled to the main clutch |5| and of into highly compacted pavement as the paving machine travels or advances along the strip of pavement being laid thereby.

The compaction members 36 may be moved vertically by raising or lowering the transverse compactor elevator member |32 with respect to the transverse compactor frame member 95 to which it is slidably mounted by means of a plurality of bolts |34 which extend through round holes in the compactor elevator member |32 and vertically slotted holes in the said transverse compactor frame member 95. A spring loaded shoe |35 on each bolt |34 maintains the compactor elevator member |32 tightly against the compactor frame member 95 and yet admits of it being moved vertically with respect thereto. Suitable mechanism such as a plurality of vertical screws |36 journaled in brackets |31 supported on the transverse compactor frame member 95 operated in unison through worm and pinion gearing |38 and |39 by common transverse shaft |40 turned by a hand wheel |4| through a reduction gear box |42 admits of minute vertical adjustment of the compaction members 36 during the operation of the paving machine, which vertical adjustment comprises the raising and lowering of the curved shoe |20 and the bulldozer plate |2| with respect to the compactor sub-frame 33. This minute vertical adjustment of the compaction members 36 during the operation of the paving machine has distinct advantages which will be explained fully when describing the operation of the improved paving machine.

By employing suitable means such as a system if securing bolts |43 and spacer studs |44 beyween the shoes |20 and the base |22 of the com- Jactor arm castings |23, the lateral slope of the shoes |20 of the compaction members 36 may be adjusted to provide a transverse crown to a pavement being laid by the paver and the longitudinal slope or tilt of the shoes 20 may be changed to obtain variations in the action of the compactors on pavement laid by the machine. These adjustments are infrequent and only need be made when job conditions require and to obtain more or less area of smoothing action of the compaction members; the more the shoes |20 are tilted forward the less the smoothing action of the compaction members on the back stroke thereof.

general to the other drawing figures, the particuvthe said distributor screws 34.

controlled by a hand lever |55 and a remote control linkage generally designated by the numeral |56 in Fig. 1 turns the main drive shaft |51 at selected speeds.

A traction transmission |58 including a built in clutch |59 operated by a clutch lever |60 is operatively connected by a chain drive |6| to the main drive shaft |51. An idler shaft |62 rotated by a chain drive |63 transfers power from the traction transmission |58 through clutches |64 operated by hand levers |65, chain drives' |66, transverse shafts |61 and chain drives |68 to the caterpillar drive sprockets 52 keyed to the rear caterpillar tread sprocket shafts 49. By such mechanism or its equivalent. the paver is driven forward, reversed, and turned at will.

A chain drive |10 connects a stub shaft |1| coupled by a clutch |12 to the main drive shaft |56 to reduction gearing |13 and |14 which rotates the agitator and collector drive shaft |15 which in turn is connected by clutches 11 .operated by hand levers 18 and 19 through chain drives 16 to the sprockets 15 on the outer ends of each collector screw 29. This mechanism permits the screws 29 to be operated simultaneously or independent of each other as required to move paving material in the hopper 28 to the adjustable gates 10 and 1| thereof.

A hydraulic pump and valve unit |16 operated by a chain drive |11 from a high speed transmission shaft |540 of the main transmission |54 operates the hydraulic jacks 94 through hydraulic lines |18 and |19 whereby to raise and lower the floating sub-frame 30 to and from its transport position shown in Fig. 3.

The main source of power and main transmission, the traction transmission and drive means, the agitator collector transmission and drive means, and the hydraulic supply means are all supported on the main frame 25.

Power from the main drive shaft |51 is transmitted to a rear drive shaft through a. chain drive |8| extending from a stub shaft |82 connected by a clutch |83 to the stub shaft |1|. The transverse distributor screws 34 are each independently driven from the rear drive shaft |80 through stub shafts |84 geared to the rear drive shaft |80 and through clutches I|| and chain drives ||0 connected to sprockets |09 keyed on All of this mechanism is supported on the oating sub-frame 30.

The compactor eccentrics |25 keyed to the cornpactor drive shaft |26 are driven by a chain drive |28 which rotates the said compactor drive shaft |26 from a stub shaft |90, all of which are supported on the compactor sub-frame 33. The said stub shaft is rotated by a chain drive |92 running between the stub shaft |9| supported on the compactor sub-frame 33 and the rear drive shaft |80 supported on the floating sub-frame 30.

The various drive means herein disclosed are not a part of thisinvention, it being understood that the means for applying power to drive the various movable elements of the invention may be altered and arranged in any other desired manner without departing from the invention herein disclosed.

Operation When in use. a paver embodying the invention travels with its front wheels 26 and caterpillar endless treads 21 on the finished rough grade 200 which is the i'lne or partially graded terrain, subgrade or other base upon which concrete or asphalt pavement is to be laid by the novel paver herein disclosed.

Paving material is dumped into the hopper 28 carried by the main frame 25 and the gates 10 and 1| thereof are adjusted to admit of the proper amount of paving material to fall by gravity from the said hopper 28 into a windrow 14 as illustrated in'Figs. 2, 4, 5, 12 and 13,v the agitator and conveyor screws 29 constantly carrying paving niaterial within the hopper 28 to the center thereof. If more material is required on one side of the machine than the other due to inaccuracies of the rough grade 200, one of the gates and 1| may be opened wider than the other by manipulating the levers 12 or 13. If paving material collects in one side of the hopper 28 more than in the other, one of the agitator and conveyor screws 29 may be stopped temporarily by means of one of clutch levers 18 and 19 until the distribution of the paving material in the hopper 2-8 is equalired.

As the paver travels forward on its front wheels 26 and endless treads 2|, the transverse distributor screws 34 and strike 35 engage the windrow 14 Y of paving material and distribute it evenly along the strike 35 which has been previously adjusted to admit of the proper amount of paving material to pass thereunder as indicated in Figs. 2, 53 .9, 12 and 13, which paving material 20| is then acted upon by the compaction members 36 as hereinafter described in detail. The spring loaded riding over the finished grade '200.

forms 31 carried by the oating sub-frame 30' travel on the rough grade 200 and provide lateral margins within which paving material 20| is restricted during transverse distribution and compaction.

.The floating sub-frame 30 which carries the transverse distributor screws 34 and the strike 35 carried by the compactor sub-frame are maintained in the desired floating pivotal relationship to the main frame 25 bymeans of gage wheels 32 which travel on the finished pavement 202, the adjustment of the gates 10 and 1| of the hopper 28 and the strike 35 having been made in contemplation of the thickness of pavement to be laid by the paving machine. y

The action of the compaction members 36 on the paving material 20| bulldozes-with the bulldozer plates |20 that portion of the paving material 20| ahead of the said compaction members 36 which is not required to produce a dense compact and substantially voidless finished pavement 202. The required paving material to produce the finished pavement 202 slides under the curved shoe |20 of the compaction members 36 during the simultaneous forward stroke of the compaction members 36 and forward movement of the paver. The downward stroke of the. compaction members 3-6 then compacts the paving material 20| and the rearward stroke thereof kneads and further compresses the said paving material into a solid compact substantially voidless pavement 202. The

subsequent upward stroke of the compaction` members 36 then completes the cycle of the said compaction members 36. The compaction action of the compaction members 36 is preferably quite rapid, for example, 150 to 300 complete cycles per minute has been found to be desirable; the type of pavement being laid and temperatures thereof generally govern the rate vof movement of the finished pavement 202 at the gage wheels 32 which causes the said finished pavement 202 to become thicker as the machine moves forward. Fig. 13 shows the compaction members 36 lowered with respect to the top of the finished pavement 202 at the gage wheels 32 whichvcauses the finished pavement 202 to become thinner as the machine moves forward. When the bottom of the compaction members 36 is level with the tread of the gage wheels 32 at the pavement 202, then, a constant thickness of pavement is laid by the machine subject to slight variations of the main frame 25 Fine adjustment of the elevation of the compaction members 36 is accomplished by turning the hand wheel |4| which raises and lowers the compactor eievator member |32 from which the forward ends of the compaction members 36 are suspended.

By pivotally suspending the forward end of the floating sub-frame on transverse pivots within the middle third of the distance between the front wheels 26 and caterpillar endless treads 21, a minimum eiect of variations in the iinished grade 200 is had in the nished pavement 202.

'I'he entire bank of compaction members 36 are tilted/laterally by means of tilting the compactor subframe 33 with respect to the oating subframe 30, which vtilting of the sub-frame 33 is accomplished by the manipulation of levers. |04. 'I'he compaction mem-bers 36 are thus tilted to compensate for lateral tilting of the main frame due to the paver tilting laterally on'uneven nished grade 200 or soft spots therein. The pivoting of the gage wheels 32 on longitudinal pivots 89 permits the gage wheels 32 to ride the pavement irrespective of the fact that the paving machine may be tilted laterally with respect to the finished pavement, thus preventing scoring of the finished pavement by the edge or edges of the gage wheels 32. v

The improved paving machine is more accurate in laying finished concrete or asphalt or black top pavements' than earlier developed similar machines in that minute regulation Oftransverse leveling, grade, and thickness of pavement being laid thereby is within the control of the operator of the machine. The machine completely and accurately lays and compacts paving material without subsequent tamping into iinished pavement having a maximum density and complete uniformity, the machine 'being capable of operating under all reasonable working conditions without the use of pre-set forms. By virtue of its extreme accuracy in laying pavement to maximum density, thickness and grade, much materia-l, machine time, and hand labor is saved when laying pavement therewith.

Although but one embodiment of the invention has been disclosed and described herein, it is obvious that many changes may be made in the size, shape, arrangement and details of the various elements of the invention without departing from the spirit thereof -and it is not intended to limit the scope of the invention other than by the terms of the appended claims.

I claim:

1. In a paving machine of the class described,

a main frame including mobile means therefor, a sub-frame connected to the said main frame for combined vertical and lateral tilting movement with respect thereto and towed thereby, a cornpactor sub-frame carried by the first-mentioned sub-frame and including means for raising and lowering and laterally tilting the said compactor sub-frame with respect to said first-mentioned sub-frame, a series of compaction members each composed of a bottom `shoe and a front bulldozer plate disposed transversely of said compactor subframe, a single line of linkage elements suspending said compaction members from said compactor sub-frame pivoted on transversely disposed pivots at their upper and lower ends respectively to said compactor sub-frame and said compaction members, an eccentric shaft parallel to said pivots including eccentrics mounted thereon, and rear wardly and upwardly disposed arms connecting said compaction members with said eccentrics.

2. In a paving machine of the class described, a main frame including mobile means therefor, a sub-frame pivoted on transverse pivots to the said main frame and towed thereby, said transverse pivots being free to float vertically relative to said main frame, a compactor sub-frame carried by first-mentioned sub-frame and including means for raising and lowering and laterally tilting the said compactor sub-frame with respect to said first-mentioned sub-frame, a series of compaction members each composed of a bottom shoe and a front bulldozer plate disposed transversely of said compactor sub-frame, a single line of linkage elements suspending said compaction members from said compactor sub-frame pivoted on transversely disposed pivots at their upper and l lower ends respectively to said compactor subframe and said compaction members, an eccentric shaft parallel to said pivots including eccentrics mounted thereon, rearwardly and upwardly disposed arms connecting said compaction members with said eccentrics, and means for raising and lowering the said compaction member linkage elements with respect to said compactor subframe.

3. In a paving machine of the class described, a main frame including mobile means therefor traveling on the finished grade over which pavement is to be laid, a sub-frame pivoted on transverse pivots to the said main frame and towed thereby, said transverse pivots being free to float vertically relative to said main frame, a compactor sub-frame carried by the first-mentioned sub-frame and including means for raising and lowering and laterally tilting the said compactor sub-frame with respect to said first-mentioned sub-frame, a series of compaction members each composed of a bottom shoe and a front bulldozer plate disposed transversely of said compactor sub-frame, a single line of linkage elements suspending said compaction members from said compactor sub-frame pivoted on transversely disposed pivots at their upper and lower ends respectively to said compactor sub-frame and said compaction members, an eccentric shaft parallel to said pivots including eccentrics mounted thereon, rearwardly and upwardly disposed arms connecting said compaction members with said eccentrics, and gage means carried on the rear of the said first-mentioned sub-frame mobile on pavement laid by said paving machine and floating therewith in all directions.

4. In a paving machine of the class described, a main frame 'including mobile means therefor traveling on the finished grade over which pavement is to be laid, a sub-frame connected to the said main frame for combined vertical and lateral Vtilting movement with respect thereto and towed thereby, a compactor sub-frame carried by the first-mentioned sub-frame and including means for raising and lowering and laterally tilting the said compactor sub-frame with respect to said first-mentioned sub-frame, a series of compaction members each composed of a bottom shoe and a front bulldozer plate disposed transversely of said compactor sub-frame, a single line of linkage elements suspending said compaction members from said compactor sub-frame pivoted on transversely disposed pivots at their upper and lower l ends respectively to said compactor sub-frame and said compaction members, an eccentric shaft parallel to said pivots including eccentrics mounted thereon, rearwardly and upwardly disposed arms connecting said compaction members with said eccentrics, and gage rollers carried by said first-mentioned sub-frame mobile on pavement laid by said paving machine and pivoted on vertical and longitudinal pivots in trailing casterlike relationship to said first-mentioned subframe.

5. In a paving machine of the class described, a main frame including mobile means therefor traveling on the finished grade over which pavement is to be laid, a sub-frame pivoted on transverse pivots to the said main frame and towed thereby, a connection between said pivots and said main frame allowing free vertical movement of said pivots relative to said main frame, a compactor sub-frame carried by the first-mentioned sub-frame and including means for raising and lowering and laterally tilting the said compactor sub-frame with respect to said first-mentioned sub-frame, a series of compaction members each composed of a bottom shoe and a front bulldozer plate disposed transversely of said compactor subframe, a single line of linkage elements suspending said compaction members from said compactor sub-frame pivoted on transversely disposed pivots at their upper and lower ends respectively to said compactor sub-frame and said compaction members, an eccentric shaft parallel to said pivots including eccentrics mounted thereon, rearwardly and upwardly disposed arms connecting said compaction members with said eccentrics, means for raising and lowering the said compaction member linkage elements with respect to said compaction sub-frame, gage rollers carried by said floating sub-frame mobile on pavement laid by said paving machine and pivoted on vertical and longitudinal pivots in trailing caster-like relationship to said rst-mentioned sub-frame, and resilient means for constantly urging said gage rollers to a position laterally parallel to said first-mentioned subframe.

6. In a paving machine of the class described, a main frame including mobile means therefor,

' a hopper carried by said main frame including means for paying out paving material to be laid by the paving machine, a floating sub-frame pivoted on freely vertically shiftable transverse pivots to the said main frame and towed thereby, means carried by said oating sub-frame for spreading paving material payed out of said hopper across the machine, a compactor sub-frame carried lby the first-mentioned sub-frame and including means for raising and lowering and laterally tilting the said compactor sub-frame with respect to first-mentioned sub-frame, a strike carried by said compactor sub-frame to strike off paving material to the desired thickness, and a series of compaction members carried by and disposed transversely 'of said compactor sub-frame adapted'to-compact and smooth paving material spread thereahead, and gage means carried on the rear of the rst mentioned sub-frame mobile on pavement laid by said paving machine.

7. Inr a paving machine of the class described, a mainframe including mobile means therefor, a hopper carried by said main frame including means for paying out paving material to be laid by the paving machine, a floating sub-frame pivoted on freely vertically shiftable transverse pivots to the said main frame and towed thereby, means carried by said sub-frame for spreading paving material payed out of -said hopper across the machine, a compactor sub-frame carried by the first-mentioned sub-frame and including meansv for raising and lowering and laterally tilting the said compactor sub-frame with respect to said first-mentioned sub-frame, a strike carried by said compactor sub-frame to strike off paving material to the desired thickness, a series of compaction members carried by and disposed transversely of said compactor sub-frame adapted to compact and smooth Ipaving material spread thereahead, means for raising and lowering the said compaction members with respect to said compactor sub-frame, gage means carried on the rear of the said first-mentioned sub-frame mobile on pavement;l laid by said paving machine, and means carried by said main frame for tilting said rst-mentioned sub-frame upwardly about its pivots whereby to increase the mobility to said machine when not in use.

8. In a paving machine 0f the class described, a main frame, means for movably supporting said main frame, means carried by said main frame for driving said supporting means, means on said main frame for receiving material to be spread on a road-bed and applying said material to a road-bed'in predetermined relation with respect thereto, a sub-frame pivoted to said main frame in trailing relation with respect thereto, a plurality of mechanically driven means carried by said sub-frame operable on said material applied to said road-bed by the third-mentioned means to compact the same on said road-bed, means for driving said mechanically driven means from'the second-mentioned means during driving of the first-mentioned means and means connected to said sub-frame positioned to travel on said material compacted by the last-mentioned means for controlling the level of operation of said lastmentioned means.

9. In a paving machine of the class described, a main frame, meansfor movably supporting said main frame, means carried by said main frame for driving said supporting means, means on said main frame for receiving material to lbe spread on a road-bed and applying said material to a road-bed in predetermined relation with respect thereto, a sub-frame pivoted to said main frame in trailing relation with respect thereto, a plu-v rality of mechanically driven means carried by said sub-frame operable on said material applied to said road-bed by the third-mentioned means to compact the same on said road-bed, means for vdriving said mechanically driven means from the y second-mentioned means during driving of the 'rst-mentioned means and means positioned to travel on said material compacted by the lastmentioned means for controlling the level of operation of said last-mentioned means comprising rollers carried by said sub-frame in trailing relation with respect thereto.

r ROBERT D. BAKER. 

